Thousands of Arizona mines have boomed and busted in the state’s history.

Now, decades after the heyday, the federal government and scientists are working to keep humans out of abandoned sites while still inviting bats in.

“In the absence of these abandoned mine habitats, these bat populations would crash,” said Arizona Game and Fish research ecologist Joel Diamond.

Diamond spoke as he drove through the desert near Buckeye. The area’s popular with recreational shooters and four-wheelers.

The opening to a former silver mine appears without warning. It’s a 90-foot drop to the bottom.

(Photo by Mariana Dale - KJZZ)

Arizona Game and Fish research ecologist Joel Diamond says wildlife including javelina, bobcats, ringtails and mountain lions have been known to take refuge in abandoned mines, especially in the summer months.

“The shaft's deep enough that it’s a one-way trip,” Diamond said. “If you fall in the shaft, you’re probably not going to make it back out.”

Game and Fish worked with federal partners to block off the mine last year. The opening is ringed by a metal culvert and rebar forms a grid pattern on the top.

The design lets bats fly through and keeps desert tortoises and other animals, including people, from walking in.

“Before we gated it, it was something you could drive your ATV right into and not notice because it was level with the ground,” Diamond said.

Bats need a variety of habitats to live out their lives. Caves often have multiple microclimates, which makes them suitable for multiple purposes such as a nursery for pups or daytime hangout.

“We usually prioritize on if it seems like there’s a lot of public access where people could get hurt,” said Misty Shafiqullah, who manages Arizona’s abandoned-mine lands program for the BLM. “That’s where we’re going to put our money first.”

“A lot of these things can be picked up with satellite imagery, but you’re not going to see all of them that way and so you really do have to get out on the ground to find a lot of them,” Shafiqullah said.

On a recent January day, BLM staffers joined contractors and Jason Corbett from Bat Conservation International to walk through a planned mine gate site near Parker.

BLM geologist Vince Beresford points out a stripe of turquoise-colored mineral on the rocks.

“When they started out prospecting, they probably noticed a vein of some sort of Chrysocolla at the surface and then wanted to follow that into the ground.”

The Chrysocolla vein marked a copper deposit.

The miner’s pursuit of the metal left the hillside pitted with openings.

Contractor Tom Gilleland measures each one for a custom-fit gate. His business Mine Gates Environmental relies almost solely on federal contracts. He said funding for these types of projects has dried up under the current federal administration.

“I literally just did my taxes and our revenues were half of what they were last year,” Gilleland said.

The walkthrough that brought everyone to Parker was almost canceled because of the government shutdown.

After donning a helmet, Corbett leads the group into a rocky crevice where the ceiling is just a few feet overhead.

(Photo by Mariana Dale - KJZZ)

Jason Corbett said he's found people living in abandoned mines. This one near Parker just had a hodge podge of trash.

The cramped space is full of trash — a sign that people are also drawn to the area. A nearby gate is riddled with holes like someone used it for target practice.

Arizona Game and Fish research ecologist Joel Diamond says wildlife including javelina, bobcats, ringtails and mountain lions have been known to take refuge in abandoned mines, especially in the summer months. (Photo by Mariana Dale - KJZZ)

An example of a mine gate in the desert near Buckeye. The raised edge keeps animals such as tortoises from accidentally walking in. (Photo by Mariana Dale-KJZZ)

This 90-foot shaft once lead to a silver mine, now it's a nighttime feeding spot for California leaf-nosed bats. (Photo by Mariana Dale-KJZZ)

A stripe of blue-green Chrysocolla could indicate a copper deposit in the rock nearby. (Photo by Mariana Dale-KJZZ)

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